The development of thin, dense, defect-free solid electrolyte
films
is key for achieving practical and commercially viable solid-state
batteries. Herein, we showcase a facile processing pathway for antiperovskite
(Li2OHCl) solid electrolyte materials that can yield films/pellets
with very high densities (∼100%) and higher conductivities
compared with conventional uniaxially pressed pellets. We have also
achieved close to 50% improvement in the critical current density
of the material and an improved lithiophilicity due to the surface
nitrogen enrichment of the processed pellets. Distribution of relaxation
time analysis supports the contributions from “faster”
transport mechanisms for the antiperovskite films/pellets developed
using the new protocol. Overall, the results highlight the feasibility
of our new processing pathway for engineering antiperovskite solid
electrolytes at the grain scale as a highly desirable approach for
practical all-solid-state batteries